Re: [PATCH v7] rust: transmute: Add methods for FromBytes trait

[kernel test robot <lkp@intel.com>]

Hi Every2,

kernel test robot noticed the following build errors:

[auto build test ERROR on rust/rust-next]
[also build test ERROR on linus/master v6.16-rc1 next-20250613]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Every2/rust-transmute-Add-methods-for-FromBytes-trait/20250615-152228
base:   https://github.com/Rust-for-Linux/linux rust-next
patch link:    https://lore.kernel.org/r/20250615072042.133290-1-christiansantoslima21%40gmail.com
patch subject: [PATCH v7] rust: transmute: Add methods for FromBytes trait
config: um-randconfig-001-20250615 (https://download.01.org/0day-ci/archive/20250616/202506160013.MgafgaAm-lkp@intel.com/config)
compiler: clang version 21.0.0git (https://github.com/llvm/llvm-project f819f46284f2a79790038e1f6649172789734ae8)
rustc: rustc 1.78.0 (9b00956e5 2024-04-29)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250616/202506160013.MgafgaAm-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202506160013.MgafgaAm-lkp@intel.com/

All errors (new ones prefixed by >>):

>> error[E0046]: not all trait items implemented, missing: `from_bytes`, `from_mut_bytes`
   --> rust/doctests_kernel_generated.rs:3156:1
   |
   3156 | unsafe impl kernel::transmute::FromBytes for MyStruct{};
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `from_bytes`, `from_mut_bytes` in implementation
   |
   = help: implement the missing item: `fn from_bytes(_: &[u8]) -> Option<&Self> { todo!() }`
   = help: implement the missing item: `fn from_mut_bytes<Self>(_: &mut [u8]) -> Option<&mut Self> where Self: AsBytes { todo!() }`
--
>> error[E0046]: not all trait items implemented, missing: `from_bytes`, `from_mut_bytes`
   --> rust/doctests_kernel_generated.rs:3221:1
   |
   3221 | unsafe impl kernel::transmute::FromBytes for MyStruct{};
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `from_bytes`, `from_mut_bytes` in implementation
   |
   = help: implement the missing item: `fn from_bytes(_: &[u8]) -> Option<&Self> { todo!() }`
   = help: implement the missing item: `fn from_mut_bytes<Self>(_: &mut [u8]) -> Option<&mut Self> where Self: AsBytes { todo!() }`
--
>> error[E0599]: no function or associated item named `from_bytes` found for type `u32` in the current scope
   --> rust/doctests_kernel_generated.rs:9216:19
   |
   9216 | let result = u32::from_bytes(&arr);
   |                   ^^^^^^^^^^ function or associated item not found in `u32`
   |
   = help: items from traits can only be used if the trait is in scope
   help: trait `FromBytes` which provides `from_bytes` is implemented but not in scope; perhaps you want to import it
   |
   3    + use crate::rust_doctest_kernel_alloc_kbox_rs_7::kernel::transmute::FromBytes;
   |
   help: there is an associated function `from_be` with a similar name
   |
   9216 | let result = u32::from_be(&arr);
   |                   ~~~~~~~
--
>> error[E0046]: not all trait items implemented, missing: `from_bytes`, `from_mut_bytes`
   --> samples/rust/rust_dma.rs:35:1
   |
   35 | unsafe impl kernel::transmute::FromBytes for MyStruct {}
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `from_bytes`, `from_mut_bytes` in implementation
   |
   = help: implement the missing item: `fn from_bytes(_: &[u8]) -> Option<&Self> { todo!() }`
   = help: implement the missing item: `fn from_mut_bytes<Self>(_: &mut [u8]) -> Option<&mut Self> where Self: AsBytes { todo!() }`

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